White Saum - rivulatus or stalsbergi?

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THQ said:
It has a silver edge so it's not a Rivulatus (gold edge),
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That is not true. The color of the tail trim is a polymorphic trait in rivulatus. It has been well known for many years now, that white and gold trim even come from the same wild populations of rivulatus.
Blombergi is a rare fish in the hobby. It typically has a very narrow tail trim, unlike the fish in question. With out a known collection point, no reason to suppose the fish in question is blombergi. The scale pattern does not differ between these 2 species; only stalbergi has the very different reverse scale pattern.
The white trimmed rivulatus are very common; even a couple years back they were more common at the box stores then the gold trimmed, for at least a couple years.
 
The OP's GT is a white saum Rivulatus. The white and orange saum Rivulatus were about 50/50 in the 80s when the fish were first introduced. It was reported then that both white and orange offspring came out of orange parents. The whilte saum was considered lower quality GT and over time, the white saum was line bred out of the stock. Today, you can't find any white saum from Asian stock, but white saum reappear by regression in Florida stock. The GT in my avatar is an Asian stock and its offspring are 100% orange.
 
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Thanks for all the information guys. No LFS within 100 miles of me hardly carry any variant of GT, and those who do only have 1" specimens that aren't able to be sexed. I feel like I found a diamond when I walked into my LFS and found this male.

Benno87 said:
He needs a few good feeds judging by how skinny he is
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Indeed! He gobbles up whatever I put in the tank readily, and have been feeding a bit of hex guard and monitoring his feces. Seems to be just underweight!
 
OK, I stand corrected. I have never seen a white edged rivulatus in my country before.
 
Everything is pretty well covered already. Stalsbergi are actually plainly distinctive from white edged rivulatus once you understand (and see) that the difference is in the scale edges and centers, not in them having white fin edges. There's a lot of confusion on forums on these fish. If you're interested in getting it straight. along with some of the history, I'd suggest reading this Wayne Leibel article and also checking Alf Stalsbergi's Andinoacara page.

Basically, rivulatus is the Ecuadoran fish (and can be white or gold edged) and Staslbergi are found in Peru. Note the German article quoted in Leibel's article that called what they mistakenly thought was rivulatus and what we now know as stalsbergi: "The Green Terror That Isn't". The notion that rivulatus wasn't the 'true' or 'original' green terror comes from confusion over which was true rivulatus, which is what some thought stalsbergi to be. But that turned out to be wrong, stalsbergi were not the true rivulatus, but they were the 'green terror that isn't' in the German article.
 
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BC in SK said:
That is not true. The color of the tail trim is a polymorphic trait in rivulatus. It has been well known for many years now, that white and gold trim even come from the same wild populations of rivulatus.
Blombergi is a rare fish in the hobby. It typically has a very narrow tail trim, unlike the fish in question. With out a known collection point, no reason to suppose the fish in question is blombergi. The scale pattern does not differ between these 2 species; only stalbergi has the very different reverse scale pattern.
The white trimmed rivulatus are very common; even a couple years back they were more common at the box stores then the gold trimmed, for at least a couple years.
Click to expand...
 
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